The Horsham Preservation and Historical Association (HPHA), founded in 1997, is dedicated to identifying, studying, preserving and protecting the historical heritage, buildings and artifacts of the Horsham area. Horsham Township began as a farming and residential community. For many years, the Willow Grove Naval Air Station was Horsham's largest employer and its most recognized feature. The predecessor of the Air Station was the Pitcairn Airfield, where Harold Pitcairn built the Mailwing airplane, delivered airmail along the East Coast, formed Eastern Air Lines, developed the Autogiro, and entertained celebrities such as Charles Lindbergh and Amelia Earhart.